Handle Ethereum provider errors

[Nebulis]

In the case of Infura rate limit:

[{"type":"DOCUMENT_INTEGRITY","name":"OpenAttestationHash","data":true,"status":"VALID"},{"name":"OpenAttestationEthereumDocumentStoreIssued","type":"DOCUMENT_STATUS","data":{"issuedOnAll":false,"details":[{"issued":false,"address":"0xdcA6Eea7024151c270b50FcA9E67161119B06BAD","reason":{"message":"Error with smart contract 0xdcA6Eea7024151c270b50FcA9E67161119B06BAD: undefined","code":3,"codeString":"ETHERS_UNHANDLED_ERROR"}}]},"reason":{"message":"Error with smart contract 0xdcA6Eea7024151c270b50FcA9E67161119B06BAD: undefined","code":3,"codeString":"ETHERS_UNHANDLED_ERROR"},"status":"INVALID"},{"status":"SKIPPED","type":"DOCUMENT_STATUS","name":"OpenAttestationEthereumTokenRegistryMinted","reason":{"code":4,"codeString":"SKIPPED","message":"Document issuers doesn't have \"tokenRegistry\" property or TOKEN_REGISTRY method"}},{"name":"OpenAttestationEthereumDocumentStoreRevoked","type":"DOCUMENT_STATUS","data":{"revokedOnAny":true,"details":[{"revoked":true,"address":"0xdcA6Eea7024151c270b50FcA9E67161119B06BAD","reason":{"message":"Error with smart contract 0xdcA6Eea7024151c270b50FcA9E67161119B06BAD: undefined","code":3,"codeString":"ETHERS_UNHANDLED_ERROR"}}]},"reason":{"message":"Error with smart contract 0xdcA6Eea7024151c270b50FcA9E67161119B06BAD: undefined","code":3,"codeString":"ETHERS_UNHANDLED_ERROR"},"status":"INVALID"},{"status":"SKIPPED","type":"ISSUER_IDENTITY","name":"OpenAttestationDnsTxt","reason":{"code":2,"codeString":"SKIPPED","message":"Document issuers doesn't have \"documentStore\" / \"tokenRegistry\" property or doesn't use DNS-TXT type"}},{"type":"ISSUER_IDENTITY","name":"OpencertsRegistryVerifier","status":"VALID","data":[{"status":"VALID","value":"0xdcA6Eea7024151c270b50FcA9E67161119B06BAD","name":"ROPSTEN: Government Technology Agency of Singapore (GovTech)","displayCard":false}]}]

In the case of Cloudflare's random 502 bad request error:

[{"type":"DOCUMENT_INTEGRITY","name":"OpenAttestationHash","data":true,"status":"VALID"},{"status":"SKIPPED","type":"DOCUMENT_STATUS","name":"OpenAttestationSignedProof","reason":{"code":4,"codeString":"SKIPPED","message":"Document does not have a proof block"}},{"name":"OpenAttestationEthereumDocumentStoreIssued","type":"DOCUMENT_STATUS","data":{"issuedOnAll":true,"details":[{"issued":true,"address":"0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f"}]},"status":"VALID"},{"status":"SKIPPED","type":"DOCUMENT_STATUS","name":"OpenAttestationEthereumTokenRegistryMinted","reason":{"code":4,"codeString":"SKIPPED","message":"Document issuers doesn't have \"tokenRegistry\" property or TOKEN_REGISTRY method"}},{"name":"OpenAttestationEthereumDocumentStoreRevoked","type":"DOCUMENT_STATUS","data":{"revokedOnAny":true,"details":[{"revoked":true,"address":"0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f","reason":{"message":"Error with smart contract 0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f: bad response","code":3,"codeString":"ETHERS_UNHANDLED_ERROR"}}]},"reason":{"message":"Error with smart contract 0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f: bad response","code":3,"codeString":"ETHERS_UNHANDLED_ERROR"},"status":"INVALID"},{"status":"SKIPPED","type":"ISSUER_IDENTITY","name":"OpenAttestationDnsTxt","reason":{"code":2,"codeString":"SKIPPED","message":"Document issuers doesn't have \"documentStore\" / \"tokenRegistry\" property or doesn't use DNS-TXT type"}},{"type":"ISSUER_IDENTITY","name":"OpencertsRegistryVerifier","status":"VALID","data":[{"status":"VALID","value":"0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f","name":"Singapore Examinations and Assessment Board","displayCard":true,"website":"https://www.seab.gov.sg/","email":"","phone":"+65 6872 2220","logo":"/static/images/SEAB_logo_crop.png","id":"seab-registry"}]}]

In the case of Cloudflare 429 rate limit error:

[{"type":"DOCUMENT_INTEGRITY","name":"OpenAttestationHash","data":true,"status":"VALID"},{"status":"SKIPPED","type":"DOCUMENT_STATUS","name":"OpenAttestationSignedProof","reason":{"code":4,"codeString":"SKIPPED","message":"Document does not have a proof block"}},{"name":"OpenAttestationEthereumDocumentStoreIssued","type":"DOCUMENT_STATUS","data":{"issuedOnAll":false,"details":[{"issued":false,"address":"0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f","reason":{"message":"Error with smart contract 0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f: bad response","code":3,"codeString":"ETHERS_UNHANDLED_ERROR"}}]},"reason":{"message":"Error with smart contract 0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f: bad response","code":3,"codeString":"ETHERS_UNHANDLED_ERROR"},"status":"INVALID"},{"status":"SKIPPED","type":"DOCUMENT_STATUS","name":"OpenAttestationEthereumTokenRegistryMinted","reason":{"code":4,"codeString":"SKIPPED","message":"Document issuers doesn't have \"tokenRegistry\" property or TOKEN_REGISTRY method"}},{"name":"OpenAttestationEthereumDocumentStoreRevoked","type":"DOCUMENT_STATUS","data":{"revokedOnAny":true,"details":[{"revoked":true,"address":"0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f","reason":{"message":"Error with smart contract 0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f: bad response","code":3,"codeString":"ETHERS_UNHANDLED_ERROR"}}]},"reason":{"message":"Error with smart contract 0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f: bad response","code":3,"codeString":"ETHERS_UNHANDLED_ERROR"},"status":"INVALID"},{"status":"SKIPPED","type":"ISSUER_IDENTITY","name":"OpenAttestationDnsTxt","reason":{"code":2,"codeString":"SKIPPED","message":"Document issuers doesn't have \"documentStore\" / \"tokenRegistry\" property or doesn't use DNS-TXT type"}},{"type":"ISSUER_IDENTITY","name":"OpencertsRegistryVerifier","status":"VALID","data":[{"status":"VALID","value":"0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f","name":"Singapore Examinations and Assessment Board","displayCard":true,"website":"https://www.seab.gov.sg/","email":"","phone":"+65 6872 2220","logo":"/static/images/SEAB_logo_crop.png","id":"seab-registry"}]}]

Edit (20 Aug): Found another interesting response: "missing response"

[{"type":"DOCUMENT_INTEGRITY","name":"OpenAttestationHash","data":true,"status":"VALID"},{"status":"SKIPPED","type":"DOCUMENT_STATUS","name":"OpenAttestationSignedProof","reason":{"code":4,"codeString":"SKIPPED","message":"Document does not have a proof block"}},{"status":"SKIPPED","type":"DOCUMENT_STATUS","name":"OpenAttestationEthereumTokenRegistryStatus","reason":{"code":4,"codeString":"SKIPPED","message":"Document issuers doesn't have \"tokenRegistry\" property or TOKEN_REGISTRY method"}},{"name":"OpenAttestationEthereumDocumentStoreStatus","type":"DOCUMENT_STATUS","data":{"issuedOnAll":false,"details":{"issuance":[{"issued":false,"address":"0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f","reason":{"message":"Error with smart contract 0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f: missing response","code":3,"codeString":"ETHERS_UNHANDLED_ERROR"}}]}},"reason":{"message":"Error with smart contract 0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f: missing response","code":3,"codeString":"ETHERS_UNHANDLED_ERROR"},"status":"INVALID"},{"status":"SKIPPED","type":"ISSUER_IDENTITY","name":"OpenAttestationDnsTxt","reason":{"code":2,"codeString":"SKIPPED","message":"Document issuers doesn't have \"documentStore\" / \"tokenRegistry\" property or doesn't use DNS-TXT type"}},{"type":"ISSUER_IDENTITY","name":"OpencertsRegistryVerifier","status":"VALID","data":[{"status":"VALID","value":"0xE4a94Ef9C26904A02Cd6735F7D4De1D840146a0f","name":"Singapore Examinations and Assessment Board","displayCard":true,"website":"https://www.seab.gov.sg/","email":"","phone":"+65 6872 2220","logo":"/static/images/SEAB_logo_crop.png","id":"seab-registry"}]}]

[gjj]

This has been fixed in #544